At `627^(@)C` and `1` atm `SO_(3)` is partially dissociated into `SO_(2)` and `O_(2)` by the reaction
`SO_(3)(g)hArrSO_(2)(g)+1//2O_(2)(g)`
The density of the equilibrium mixture is `0.925 g L^(-1)`. What is the degree of dissociation?

Explanation

For equilibrium mixture , `PV=w/m"RT", " " M.wt_"mixture"="wRT"/"VP"`
`w/V` = 0.925g/L, T=900 K , P=1 atm , R=0.0821
`M.wt_"mixture"=(0.925xx0.0821xx900)/1=68.35`
Experimental m wt.of `SO_3` mixture = 68.35, Normal m.wt. of `SO_3` = 80
`{:(,SO_3 hArr, SO_2+, 1/2O_2),("Mole before equilibrium 1", 0,0,),("Mole of equilibrium" , (1-alpha), alpha , alpha//2):}`
`therefore "Normal m.wt"/"Apparent m.wt."=1+alpha/2, 1+alpha /2 =80/68.35, alpha = 0.3408` or 34.08%